Master Lock. Designed as a standard deadbolt with a patented new security feature, the NightWatch Deadbolt keeps intruders out, even if they have your key. To activate, lock the deadbolt as usual, then pull the lever while depressing a safety release that prevents accidental activation. In this “engaged” position, the NightWatch blocks out any key and is impossible to pick. The lock is engaged and disengaged from indoors only. 414.571.5625. www.masterlock.com.